The high strength carbon steels such as API X65 is widely used to build the pipelines. In this study, the corrosion behavior welds region of the gas pipeline was studied. For this purpose, Shield Metal Arc Welding (SMAW) was used to evaluate the proposed method. The welding processes were performed with E6010, E6013, and ER70S-6 electrodes as filler metal and welding carried out in 3 passes by ...

In the present study, effect of inclusions characteristics changing on the formation of acicular ferrite in submerged arc welding of API5l-X65 low alloy steel was investigated. Three different welding fluxes with different chemical composition and basicity index of 0.72, 0.82 and 0.99, and two different welding heat inputs of 1.6 kJ / mm and 2.4 kJ / mm were used to create inclusions with diffe...

The oil and gas industry is involved with severe corrosive/sour environmental conditions due to H2S, CO2, moisture content. National Association of Corrosion Engineers (NACE) has developed standards enable users select suitable materials for given sour which utilize laboratory testing. A failed piping sample (API-5L-X65) was removed from a pipeline after 15 years service. Optical microscopy use...

Oil and gas pipelines manufactured from API-5L Grade X65 steel are generally subjected to cyclic loading their internal surfaces frequently exposed corrosive sour fluids. Exposure of these environments often leads localized corrosion (pitting) decreased fatigue life. Corrosion pits geometrical discontinuities that may promote cracking by acting as stress raisers. In order optimize asset inspect...

The effect of surface roughness on corrosion behaviour carbon steel under intermittent oil/water wetting with different flow conditions was investigated by an “alternate cell”, combining potentiostatic polarisation, contact angle measurement, and computational fluidic dynamics (CFD) analysis. Under static conditions, the rough increased oil film lifetime consequently mitigated as has good adhes...